在中孔中纳米封闭的α-氨酶的活性和稳定性
Muhammad Naeem Iqbal1, Aleksander Jaworski1, Arthur C Pinon2
1Department of Materials and Environmental Chemistry, Stockholm University, Stockholm SE-106 91, Sweden.
ACS materials Au
|December 13, 2023
概括
半孔性二氧化颗粒 (MSP) 通过封装酶来增强α-氨酶的活性和稳定性. 这种性能改善是由于物理效应,而不是酶失活,这与之前的假设相反.
科学领域:
- 生物化学和材料科学 材料科学
- 酶动力学和多孔材料的酶动力学
背景情况:
- 半孔二氧化颗粒 (MSP) 正在研究治疗应用,特别是在治疗肥胖和糖尿病方面.
- 之前的研究表明,MSP通过吸附α-氨酶来减少粉消化,这意味着酶失活.
研究的目的:
- 测试MSP (SBA-15) 对α-氨酶酶酶去活化的假设.
- 使用小基板 (CNP-G3) 在MSP中纳入时测量α-氨酶活性和稳定性.
主要方法:
- 酶动力学测试使用α-氨酶,MSP (SBA-15) 和一个小基质 (CNP-G3) 进行.
- 量化了alpha-amylase在MSP上的生物吸收.
- 核磁共振 (NMR) 光谱 (1H快速MAS,13C/15N动态核极化MAS) 用于探测酶结构和环境.
主要成果:
- 与溶液中的自由酶相比,孔内纳入的α-氨酶表现出更高的活性和稳定性.
- 显著的阿尔法-氨酶的生物吸收 (大约. 21% w/w) 到MSPs被观察到,具有高的Vmax和KM值.
- 观察到的大基质 (粉) 的活性降低归因于基质大小被排除在MSP毛孔之外,而不是酶失活.
结论:
- MSP通过物理限制和基质共吸收来增强α-氨酶的活性和稳定性,而不是导致失活.
- 与溶液相比,酶的结构和溶解在MSP毛孔内基本保持不变.
- 这一发现澄清了之前的观察,并突出了工程酶-纳米粒子系统的潜力.
相关概念视频
Enzyme Inhibition
Inhibitors are molecules that reduce enzyme activity by binding to the enzyme. In a normally functioning cell, enzymes are regulated by a variety of inhibitors. Drugs and other toxins can also inhibit enzymes. Some inhibitors bind to the enzyme’s active site, while others inhibit enzymatic activity by binding to other sites on the protein structure.
RNA Stability
Intact DNA strands can be found in fossils, while scientists sometimes struggle to keep RNA intact under laboratory conditions. The structural variations between RNA and DNA underlie the differences in their stability and longevity. Because DNA is double-stranded, it is inherently more stable. The single-stranded structure of RNA is less stable but also more flexible and can form weak internal bonds. Additionally, most RNAs in the cell are relatively short, while DNA can be up to 250 million...
Enzymes
Inside living organisms, enzymes act as catalysts for many biochemical reactions involved in cellular metabolism. The role of enzymes is to reduce the activation energies of biochemical reactions by forming complexes with its substrates. The lowering of activation energies favor an increase in the rates of biochemical reactions.
Enzyme deficiencies can often translate into life-threatening diseases. For example, a genetic abnormality resulting in the deficiency of the enzyme G6PD...
Enzyme deficiencies can often translate into life-threatening diseases. For example, a genetic abnormality resulting in the deficiency of the enzyme G6PD...
Allosteric Proteins-ATCase
Binding sites linkages can regulate a protein's function. For example, enzyme activity is often regulated through a feedback mechanism where the end product of the biochemical process serves as an inhibitor.
Aspartate transcarbamoylase (ATCase) is a cytosolic enzyme that catalyzes the condensation of L-aspartate and carbamoyl phosphate to N-carbamoyl-L-aspartate. This reaction is the first step in pyrimidine biosynthesis. UTP and CTP, the end products of the pyrimidine synthesis pathway,...
Aspartate transcarbamoylase (ATCase) is a cytosolic enzyme that catalyzes the condensation of L-aspartate and carbamoyl phosphate to N-carbamoyl-L-aspartate. This reaction is the first step in pyrimidine biosynthesis. UTP and CTP, the end products of the pyrimidine synthesis pathway,...


